Molding cutterhead and knife



P. J. DUKES ETAL MOLDING CUTTERHEAD AND KNIFE Nov. 26, 1957 2 Sheets-Sheet 1 Filed June 10, 1954- Nov. 26, 1957 P. J. DUKES ETAL 2,

MOLDING CUTTERHEAD AND KNIFE Filed June 10; 1954 2 Sheets-Sheet 2 MOLDING CUTTERHEAD AND KNIFE Phillip 5. Dukes, Waukegan, and Herbert B. Clark,

Libertyville, Ill., assignors to Vascoloy-Ramet Corporation, a corporation of Delaware Application June 10, 1954, Serial No. 435,856

8 Claims. (Cl. 144-228) This invention relates to a molding cutterhead and knife, and is particularly concerned with a double ended cutting knife and means for mounting the knife on a cutterhead.

The device of the present invention is primarily designed for the production of wood molding strips of various sizes and shapes, but may also be used in the production of decorative edges and useful or ornamental shapes or forms in wood or other suitable materials.

In use, a set of knives, preferably three, are secured to the cutterhead with their profiled edges projecting a uniform distance beyond the periphery of the cutterhead. The cutterhead is then secured on a suitable arbor, such as a circular saw arbor, and rotated. The wood or other material is then fed into the rotating knives in the same manner that it would be fed into a circular saw blade, the cutting out of the form being accomplished by the profiled edges of the knives.

Heretofore the knives have been secured to the cutterhead by means of a machine screw which had to be removed every time a knife was removed from the cutterhead. Each knife had a single cutting edge so that one set of knives could be used only for one specific shape of molding. In other words every different cutting operation required a different set of knives.

In accordance with the present invention the knives are provided with a cutting edge at each end so that each set of knives may be used for two different shaping operations. The opposite ends of an individual knife may be for dissimilar shaping operations, or may be tor complementary operations such as a tongue and groove. When the opposite ends of the knife are complementary, one operation is completed and the knives are merely reversed to do the complementary operation.

The cutterhead of the present invention simplifies the removal and insertion of the knives by eliminating the necessity of removing the screw that holds the knife in place. Each knife is secured to the cutterhead by a lock nut which forces a clamping block against the face of the knife to hold it in place on the cutterhead. The clamping block may be of any suitable shape, but is preferably in the form of a wedge. In order to remove the knife it is necessary only to turn the lock nut a few turns and the knife may be removed without otherwise disturbing the securing means. After the knife has been reversed or a different knife has been positioned on the cutterhead, a few turns of the lock nut in the opposite direction will clamp it in place.

In one embodiment of the invention the cutting edge of the knife is located by the interengagement of a slot in the face of the knife and a locating protuberance, such as a pin, integral with the cutterhead. In another embodiment the cutting edge of the knife is located by the opposite edge of the knife butting against one surface of the cutterhead.

The structure of the present invention, by means of which the above and other advantages are attained, will be described in detail in the following specification, taken nited rates atent Patented Nov. 26, 1957 ice 2 in conjunction with the accompanying drawings, showing two preferred illustrative embodiments of the invention, in which:

Fig. 1 is a side elevational view of a cutterhead embodying the invention, with cutting knives secured in operative position;

Fig. 2 is a front elevation view of the cutterhead shown in Fig. 1;

Fig. 3. is a fragmentary cross sectional view showing the means for securing the cutting knife on the cutterhead;

Fig. 4 is a fragmentary perspective view of a peripheral portion of the cutterhead;

Fig. 5 is a detail perspective view of the clamping block for holding the knife against the cutterhead;

Fig. 6 is a detail perspective view of the screw which fits into a recess in the wedge;

Fig. 7 is a detail perspective view of the washer by holding position;

Fig. 8 is a detail perspective view of one form of cut- I ting knife;

Fig. 9 is a view, partly in elevation and partly insection, showing another embodiment of the cutterhead; and

Fig. 10 is a front elevational view of another form of cutting knife.

In the drawings, the cutterhead comprises a flat web or plate 2 having a centrally disposed aperture 3 provided with a bushing 4 to enable it to fit over a rotatable arbor, such as a circular saw arbor. A series of bushings detachably securable to the plate adjacent the aperture may be provided so that the cutterhead may be mounted on arbors of different sizes. A flanged rim 5 extends around the periphery of plate 2. The rim may be integral with the plate, or may be rigidly secured thereto in any suitable manner. The rim extends at right angles to the face of plate 2 to provide sulficient width for the seats against which a plurality of molding cutters or knives 6 are positioned. The rim preferably projects equally on both sides of plate 2, but may be unequal or may be positioned on only one side, if desired.

A plurality of peripheral recesses 7 are provided in the rim to accommodate the knives and the mechanism for securing them to the cutterhead. Three recesses are preferred, as shown in the drawings, but this number'may be varied. The recesses are preferably equally spaced around the rim to keep the cutterhead balanced, but the cutterhead may be balanced by proper distribution of its weight if the recesses are not equally spaced. Each recess is defined by a bottom wall 3 and a pair of side walls 9 and It) extending from opposite ends of the bottom wall to the periphery of the cutterhead. Preferably bottom wall 8 is chordal, side wall 9 extends at right angles to Wall 8, and side wall 10 extends at an acute angle to bottom wall 8, but this relationship may be varied in any desired manner. A bore 11 extending at right angles to the face of side wall 9 extends through wall 9 and rim 5. Bore 11 could be in the form of a recess extending into side wall 9, but the bore extending through rim 5 is preferred because it is easier to make. An integral protuberance 12, which serves as a locating member for knife 6, extends into recess 7 from the face of side wall 10. The wall 10 forms a seat against which knife 6 is positioned.

Knife 6 is provided with an opening 13 (Fig. 8) adapted to fit snugly on locating protuberance 12. This snug fit insures that each cutting edge projecting beyond the periphery of the cutter head is at exactly the same distance from the periphery as every other projecting cutting edge. to form cutting edges which may be complementary to each other. For example, in Fig. 8, cutting edge 14 is shapedto cut the top and' bottom edges of a board and Opposite edges 14 and 15 of knife 6 are shaped leave a projecting tongue at the center, and cutting edge is shaped to cut a groove in the center of a board. The groove is of sufiicient width and depth to receive the tongue so that adjacent edges of boards may be fitted together for flooring or any similar purpose. It will be understood that when the cutterhead is used for such purpose, all of the boards will be cut on one edge, and the knife will then be reversed to cut the opposite edge of each board. The cutting edges 14 and 15 may be unrelated to each other, and each cutting edge used as if it were on a separate knife.

A clamping block 16 is positioned in recess 7 with one face 17 arranged parallel to the inner face of side wall 10 and is pressed against knife 6. A recess 18 extends inwardly from the face 19 of clamping block 16. Recess 18 is preferably of square cross section, as shown in Fig. 5, but may have any non-circular configuration. A screw 20 having an end 21 shaped to fit the cross section of recess 18 has the end 21 positioned in recess 18. A washer 22, provided with an aperture 23 of the same shape as end 21 may be mounted on end 21 adjacent face 19 of the clamping block. If block 16 is hard enough, washer 22 is not required. The opposite end of screw 20 is seated in bore 11, and a lock nut 24 is threaded on screw 20 adjacent the inner face of side wall 9.

When nut 24 is rotated towards side wall 9 the end 21 of the screw is prevented from rotating by its interengagement with recess 18. The clamping block is restrained from rotating with screw 20 by its shape and position against knife 6. This rotation of nut 24 causes screw 20 to move longitudinally towards clamping block 16 and forces washer 22 against the block, thereby pressing the block against knife 6 to hold it firmly in place. The cutterhead is rotated on the arbor by any suitable motor (not shown), and the material to be cut is fed against the knives in the same manner it would be fed against a circular saw blade. The material is cut to the desired shape by the profiled cutting edges of the knives.

In order to remove any knife to reverse it, or to replace it with a different knife, nut 24 is given a few turns towards clamping block 16. The longitudinal movement of nut 24 away from wall 9 permits the end of screw 20 located in bore 11 to slide towards the outer end of the bore until nut 24 engages side wall 9. This movement releases the pressure against block 16 so that it can be moved away from knife 6 to provide clearance for the knife, which may then be removed from positioning protuberance 12. A different knife 6 may then be inserted laterally between face 17 of the clamping block and locating protuberance 12 which projects towards the clamping block. The opening 13 of the knife may be positioned on locating protuberance 12 and the knife may then be secured in place by rotating nut 24 in the opposite direction.

In the embodiment of Figs. 9 and 10, the structure of the cutterhead is the same as in the embodiment previously described except that the locating protuberance 12' is turned through ninety degrees so that its longest dimension is transverse to the cutterhead, and the walls 8' and 10' do not extend far enough to meet at an acute angle, but are joined by an angular wall portion 25. The knives 6' are similar to knives 6 except that opening 13' has been turned through ninety degrees so that its longest dimension extends longitudinally of the knife. Opening 13' is slightly longer than the length of locating protuberance 12' to provide a slight clearance at either longitudinal end of the opening. In this embodiment the locating protuberance serves merely to locate the knife, rather than to position it accurately, and the accurate positioning of the cutting edge of the knife is attained by butting the opposite edge of the knife against wall 25. The angular disposition of wall 25 relative to recess 7' enables either edge of a double edge knife to lie flat against the wall so that it can gauge the other edge with reference to the periphery of the cutterhead. However, if the cutting edge of a knife is of some special configuration that prevents it from lying flat against wall 25 the knife may be provided with a single cutting edge, and the opposite edge may be shaped to fit against wall 25.

In using the cutterhead of the second embodiment the knife does not have to be positioned with the same exactitude as in the first embodiment, because it may be moved laterally to butt the edge against wall 25 before the screw is rotated to tighten the knife in position. The second embodiment has another advantage in that the tolerance in manufacture is greater, because opening 13' does not have to fit snugly on locating protuberance 12.

Although we have described two embodiments of our invention in considerable detail, it will be understood that the description is intended to be illustrative, rather than restrictive, as many details of the invention may be modified or changed without departing from the spirit or scope of our invention. For example, the positions of the locating protuberance 12 and opening 13 may be reversed. It is also possible to secure nut 24 rigidly to screw 20 and to thread bore 11 so that the screw will be moved longitudinally of the recess by rotation of nut 24 and screw 20 in either direction. Accordingly, we do not desire to be restricted to the exact structure described.

We claim:

1. A cutterhead provided with a plurality of equally spaced peripheral recesses, each recess having a bottom wall, and a pair of side walls extending from said bottom wall to the periphery of said cutterhead, a bore in one of said side walls a locating protuberance of non-circular cross section projecting inwardly from the other of said side walls, a clamping block positioned in said recess, a recess of non-circular cross section in one face of said clamping block, a screw having one end of substantially the same non-circular cross section as said clamping block recess and extending into said clamping block recess and the other end of said screw extending into said bore, and a nut threaded on said screw in said cutterhead recess, said nut being operable by rotation in one direction to move said screw longitudinally to move said clamping block towards said other side wall.

2. In combination, a cutterhead and a knife, said cutterhead having a peripheral recess comprising a bottom wall, and a pair of side walls extending from said bottom wall to the periphery of said cutterhead, a locating protuberance projecting inwardly from one of said side walls, said knife having an opening engaging said locating protuberance, said protuberance and said opening having substantially the same cross sectional area and cross sectional non-circular configuration to prevent lateral and longitudinal displacement of the knife with respect to said one side wall during engagement of the knife opening with the protuberance and said knife having a cutting edge projecting beyond the periphery of said cutterhead, a clamping block in said recess and means for forcing said clamping block against said knife to hold it firmly against said one side wall.

3. In combination, a cutterhead and a knife, said cutterhead having a peripheral recess comprising a bottom wall and a side wall extending from said bottom wall to the periphery of said cutterhead, said knife being positioned transversely in said recess with a cutting edge projecting beyond the periphery of said cutterhead, a clamping block mounted in said recess, means for moving said clamping block longitudinally of said recess to press said knife against said side wall, and a locating protuberance projecting inwardly from the side wall, said knife having an opening engaging said protuberance, said protuberance and said opening having substantially the same cross sectional area and cross sectional non-circular configuration to prevent lateral and longitudinal displacement of the knife with respect to the side wall during engagement of the knife opening with the protuberance and the means for moving said clamping block being reversible to release said clamping block from pressing engagement with said knife to permit removal of said knife.

4. In combination, a cutterhead and a knife, said cutterhead having a peripheral recess comprising a bottom wall, and a pair of side walls extending from said bottom Wall to the periphery of said cutterhead, a bore in one of said side walls, a locating protuberance projecting inwardly from the other side wall, said knife being positioned transversely in said recess with a cutting edge projecting beyond the periphery of said cutterhead and having an opening engaging said locating protuberance, a clamping block mounted in said recess, a screw having one end positioned in said bore and movable longitudinally of said recess to move said clamping block to press said knife against said other side wall, said protuberance and said opening having substantially the same cross sectional area and cross sectional non-circular configuration to prevent lateral and longitudinal displacement of the knife with respect to said first mentioned side wall during engagement of the knife opening with the protuberance and said screw being reversible to release said clamping block from pressing engagement with said knife to permit removal of said knife.

5. In combination, a cutterhead and a knife, said cutterhead having a peripheral recess comprising a bottom Wall, and a pair of side walls extending from said bottom wall to the periphery of said cutterhead, a locating protuberance projecting inwardly from one of said side walls, said knife having an opening engaging said locating protuberance, said knife having two oppositely disposed cutting edges, one of said cutting edges projecting beyond the periphery of said cutterhead, said other cutting edge engaging a wall portion of said recess to gauge said first mentioned cutting edge with reference to the periphery of said cutterhead, a clamping block movably mounted in said recess, and means to force said clamping block against said knife to prevent displacement of said knife.

6. In combination, a cutterhead and a knife, said cutterhead having a peripheral recess comprising a bottom wall and a pair of side walls extending from said bottom wall to the periphery of said cutterhead, a locating protuberance projecting inwardly from one of said side walls, said knife having an opening engaging said locating protuberance, said knife having two oppositely disposed cutting edges, one of said cutting edges projecting beyond the periphery of said cutterhead, said other cutting edge engaging a wall portion of said recess to gauge said first mentioned cutting edge with reference to the periphery of said cutterhead, a clamping block movably mounted in said recess, a screw mounted for longitudinal movement in said recess, said screw engaging said clamping block, and means operable to move said screw in one direction to force said clamping block against said knife to hold it firmly against said one side Wall, said means being operable to move said screw in the opposite direction, thereby releasing said clamping block to permit removal of said knife.

7. In combination, a cutterhead and a knife, said cutterhead having a peripheral recess comprising a bottom wall and a first and second side wall each extending from said bottom wall to the periphery of said cutterhead, a locating protuberance projecting inwardly from the first side wall, said locating protuberance being non-circular in cross section, said knife having an opening of substantially the same cross section and fitting snugly on said locating protuberance, said knife having a cutting edge projecting beyond the periphery of said cutterhead, a clamping block movably mounted in said recess, said clamping block having a first face opposite a second face, each face extending parallel to one of said side Walls, the clamping block face parallel to the first side wall being positioned adjacent said knife, a recess of non-circular cross section extending into said second clamping block face, a screw having one end of substantially the same non-circular cross section as the clamping block recess fitting into said clamping block recess, a bore extending into said second side wall, the other end of said screw being movably mounted in said bore, and a nut threaded on said screw between said clamping block and said second side wall, whereby rotation of said nut in one direction forces said clamping block against said knife to hold it firmly against said first side wall and rotation in the opposite direction releases pressure of said screw against said clamping block to permit removal of said knife.

8. In combination, a cutterhead and a knife, said cutterhead having a peripheral recess comprising a bottom wall and a first and second side wall, each extending from said bottom wall to the periphery of said cutterhead, a locating protuberance projecting inwardly from the first side wall, said knife having an opening engaging said locating protuberance, said knife having a cutting edge projecting beyond the periphery of said cutterhead, a clamping block movably mounted in said recess, said clamping block having opposed faces parallel to said side walls, the clamping block face parallel to the first side wall being positioned adjacent said knife, a recess of non-circular cross-section extending into the second clamping block surface, a screw having an end portion of substantially the same noncircular cross section as said clamping block recess and fitting therein, a bore extending into the second side wall, the other end of the screw being movably mounted in said bore, and a nut threaded on said screw between said clamping block and the second side wall, whereby rotation of said nut in one direction forces said clamping block against the knife holding it firmly against the first side wall and rotation of the nut in the opposite direction releases said pressure of the screw against the clamping block permitting removal of the knife.

References Cited in the file of this patent UNITED STATES PATENTS 162,114 Streit Apr. 13, 1875 1,011,107 Blood Dec. 5, 1911 1,823,031 Dalen Sept. 15, 1931 1,830,813 Tautz Nov. 10, 1931 2,521,868 Otto Sept. 12, 1950 FOREIGN PATENTS 556,993 Great Britain Oct. 29, 1943 242,400 Switzerland Oct. 1, 1946 474,293 Canada June 5, 1951 

